We propose to employ tunable pulsed lasers (217-750 nm) to investigate: (a) resonance Raman excitation profiles of hemeproteins, including nitrosyl hemoglobin, cytochrome P-450, horseradish peroxidase and their derivatives; (b) interactions of 4-nitroquinoline-l-oxide and related carcinogens with DNA and model compounds by resonance CARS/resonance RIKES techniques; (c) effective DNA-protein cross-linking, using high power UV pulses; (d) the out-of-plane transitions (n yields pi) of polynucleotides, DNA and RNA; (e) the vibronic couplings in disulfide-containing compounds via the excitation profiles of nu(C-S) and nu(S-S); and (f) relative resonance enhancement of amide group vibrations of poly-L-lysine in various conformations, with excitatation wavelengths near 217 nm. The pulsed lasers to be employed are Molectron UV-1000/DL-200 and Chromatix CMX-4. The quantitative measurement of resonance Raman intensity relative to a non-resonance internal standard will be made by the 180 degrees backscattering geometry with a cylindrical lens to ensure the absence of "saturation effect".